On Sunday, May 29, 2022 at 2:55:43 AM UTC-7, Mikko wrote:
> On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
>
> > Where are the different stars on those maps?
> > How would you know they are two different stars?
> Copernicus, in Book Three of De revolutionibus, compares star
> catalogs from different times, and notes that latitudes of the
> stars are the same at all times but their longitudes as measured
> from the point of spring equinox or summer solstice has changed.
> Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> had confirmed more than a thousend years earler.
>
> As the equinox and solstice points of ecliptic are related to
> the poles this proves that the pole has moved. The relation
> is that the summer solstice point is the point of ecliptic that
> is the farthest from the north pole and the equinox points are
> the two points of ecliptic that are as far from the solstice
> points as they are from the poles.
>
> Hipparcos also knew that durations of the seasons are not equal.
> Later astronomers have measured that the durations of the seasons
> now are different from their durations when Hipparcos measured them.
>
> Mikko

What's really great about "the Earth is tilted to the Sun exactly 23.5
degrees" and "the Earth is in planets orbiting the Sun" and "the Moon,
of Earth, follows its usual orbit and track orbiting the Earth", is that it
really helps to set the notion "and it's always been this way in geologic
time", now though I find it incredibly fascinating, that you are really
describing anything different about the calendars, or as from
days between calendars.

Or, that's lot more wobble - star fields are "immobile, celestial, spheres".

On Sunday, May 29, 2022 at 2:30:13 PM UTC-7, Ross A. Finlayson wrote:
> On Sunday, May 29, 2022 at 2:55:43 AM UTC-7, Mikko wrote:
> > On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
> >
> > > Where are the different stars on those maps?
> > > How would you know they are two different stars?
> > Copernicus, in Book Three of De revolutionibus, compares star
> > catalogs from different times, and notes that latitudes of the
> > stars are the same at all times but their longitudes as measured
> > from the point of spring equinox or summer solstice has changed.
> > Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> > had confirmed more than a thousend years earler.
> >
> > As the equinox and solstice points of ecliptic are related to
> > the poles this proves that the pole has moved. The relation
> > is that the summer solstice point is the point of ecliptic that
> > is the farthest from the north pole and the equinox points are
> > the two points of ecliptic that are as far from the solstice
> > points as they are from the poles.
> >
> > Hipparcos also knew that durations of the seasons are not equal.
> > Later astronomers have measured that the durations of the seasons
> > now are different from their durations when Hipparcos measured them.
> >
> > Mikko
> What's really great about "the Earth is tilted to the Sun exactly 23.5

That is going to remain exact. How does gravity move an axis of rotation?
It doesn't because it would have to move the axis opposite on both sides.

Mitchell Raemsch

On Sunday, May 29, 2022 at 6:16:43 PM UTC-7, mitchr...@gmail.com wrote:
> On Sunday, May 29, 2022 at 2:30:13 PM UTC-7, Ross A. Finlayson wrote:
> > On Sunday, May 29, 2022 at 2:55:43 AM UTC-7, Mikko wrote:
> > > On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
> > >
> > > > Where are the different stars on those maps?
> > > > How would you know they are two different stars?
> > > Copernicus, in Book Three of De revolutionibus, compares star
> > > catalogs from different times, and notes that latitudes of the
> > > stars are the same at all times but their longitudes as measured
> > > from the point of spring equinox or summer solstice has changed.
> > > Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> > > had confirmed more than a thousend years earler.
> > >
> > > As the equinox and solstice points of ecliptic are related to
> > > the poles this proves that the pole has moved. The relation
> > > is that the summer solstice point is the point of ecliptic that
> > > is the farthest from the north pole and the equinox points are
> > > the two points of ecliptic that are as far from the solstice
> > > points as they are from the poles.
> > >
> > > Hipparcos also knew that durations of the seasons are not equal.
> > > Later astronomers have measured that the durations of the seasons
> > > now are different from their durations when Hipparcos measured them.
> > >
> > > Mikko
> > What's really great about "the Earth is tilted to the Sun exactly 23.5
> That is going to remain exact. How does gravity move an axis of rotation?
> It doesn't because it would have to move the axis opposite on both sides.
>
> Mitchell Raemsch

If according to Olbers sky is dark,
how does time lapse photography about pole,
always find a star at north pole?

"There's always star-light at the North and South pole(s)"?

On Sunday, May 29, 2022 at 6:17:31 PM UTC-7, Ross A. Finlayson wrote:
> On Sunday, May 29, 2022 at 6:16:43 PM UTC-7, mitchr...@gmail.com wrote:
> > On Sunday, May 29, 2022 at 2:30:13 PM UTC-7, Ross A. Finlayson wrote:
> > > On Sunday, May 29, 2022 at 2:55:43 AM UTC-7, Mikko wrote:
> > > > On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
> > > >
> > > > > Where are the different stars on those maps?
> > > > > How would you know they are two different stars?
> > > > Copernicus, in Book Three of De revolutionibus, compares star
> > > > catalogs from different times, and notes that latitudes of the
> > > > stars are the same at all times but their longitudes as measured
> > > > from the point of spring equinox or summer solstice has changed.
> > > > Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> > > > had confirmed more than a thousend years earler.
> > > >
> > > > As the equinox and solstice points of ecliptic are related to
> > > > the poles this proves that the pole has moved. The relation
> > > > is that the summer solstice point is the point of ecliptic that
> > > > is the farthest from the north pole and the equinox points are
> > > > the two points of ecliptic that are as far from the solstice
> > > > points as they are from the poles.
> > > >
> > > > Hipparcos also knew that durations of the seasons are not equal.
> > > > Later astronomers have measured that the durations of the seasons
> > > > now are different from their durations when Hipparcos measured them.
> > > >
> > > > Mikko
> > > What's really great about "the Earth is tilted to the Sun exactly 23.5
> > That is going to remain exact. How does gravity move an axis of rotation?
> > It doesn't because it would have to move the axis opposite on both sides.
> >
> > Mitchell Raemsch
> If according to Olbers sky is dark,
> how does time lapse photography about pole,
> always find a star at north pole?
>
> "There's always star-light at the North and South pole(s)"?

Who told you the sky is dark?

Mikko <mikko.levanto@iki.fi> wrote:

> On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
>
> > Where are the different stars on those maps?
> > How would you know they are two different stars?
>
> Copernicus, in Book Three of De revolutionibus, compares star
> catalogs from different times, and notes that latitudes of the
> stars are the same at all times but their longitudes as measured
> from the point of spring equinox or summer solstice has changed.
> Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> had confirmed more than a thousend years earler.

The Babylonians already knew about 'the equation of time',
both the yearly part, caused by ellipticity,
and the half-yearly part, caused by inclination.
Ptolemy had epicycles of the Sun to describe it.
There were practical applications in astrology.

> As the equinox and solstice points of ecliptic are related to
> the poles this proves that the pole has moved. The relation
> is that the summer solstice point is the point of ecliptic that
> is the farthest from the north pole and the equinox points are
> the two points of ecliptic that are as far from the solstice
> points as they are from the poles.
>
> Hipparcos also knew that durations of the seasons are not equal.

Fortunately for us summers are longer than winters.
Those Ozzies just have bad luck.

> Later astronomers have measured that the durations of the seasons
> now are different from their durations when Hipparcos measured them.

Nowadays one easily measures the day by day pole motion.
In the short term by GPS, in the long term by VLBI.
The IERS is tasked with publising the 'Earth orientation parameters',
which give both the axis orientation and the angle of rotation,

Jan

On 2022-05-30 08:17:08 +0000, J. J. Lodder said:

> Mikko <mikko.levanto@iki.fi> wrote:
>
>> On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
>>
>>> Where are the different stars on those maps?
>>> How would you know they are two different stars?
>>
>> Copernicus, in Book Three of De revolutionibus, compares star
>> catalogs from different times, and notes that latitudes of the
>> stars are the same at all times but their longitudes as measured
>> from the point of spring equinox or summer solstice has changed.
>> Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
>> had confirmed more than a thousend years earler.
>
> The Babylonians already knew about 'the equation of time',
> both the yearly part, caused by ellipticity,
> and the half-yearly part, caused by inclination.

But not about the precession.

> Ptolemy had epicycles of the Sun to describe it.

No, Ptolemy's theory of the motion of Sun (or Earth -- Ptlemy could not
determine which one is moving but choose to describe his theory in terms
of stationary Earth) did not use epicycles. Sun's motion was described
as a non-uniform motion along an eccentric circle.

> There were practical applications in astrology.

Ptolemy left unanswered one important question: what is the correct
definition of the zero point of Aries for astrological purposes?

> Fortunately for us summers are longer than winters.
> Those Ozzies just have bad luck.

Now, but it is changing.

Mikko

Mikko <mikko.levanto@iki.fi> wrote:

> On 2022-05-30 08:17:08 +0000, J. J. Lodder said:
>
> > Mikko <mikko.levanto@iki.fi> wrote:
> >
> >> On 2022-05-28 21:12:18 +0000, mitchr...@gmail.com said:
> >>
> >>> Where are the different stars on those maps?
> >>> How would you know they are two different stars?
> >>
> >> Copernicus, in Book Three of De revolutionibus, compares star
> >> catalogs from different times, and notes that latitudes of the
> >> stars are the same at all times but their longitudes as measured
> >> from the point of spring equinox or summer solstice has changed.
> >> Thus Copernicus reconfirmed what Hipparcos had suspected and Ptolemy
> >> had confirmed more than a thousend years earler.
> >
> > The Babylonians already knew about 'the equation of time',
> > both the yearly part, caused by ellipticity,
> > and the half-yearly part, caused by inclination.
>
> But not about the precession.

Indeed no, that was Hipparcos. (it takes time)

> > Ptolemy had epicycles of the Sun to describe it.
>
> No, Ptolemy's theory of the motion of Sun (or Earth -- Ptolemy could not
> determine which one is moving but choose to describe his theory in terms
> of stationary Earth) did not use epicycles. Sun's motion was described
> as a non-uniform motion along an eccentric circle.

You may well be right. I did not look at the technicalities.

> > There were practical applications in astrology.
>
> Ptolemy left unanswered one important question: what is the correct
> definition of the zero point of Aries for astrological purposes?

Didn't they lock it in Aries?

> > Fortunately for us summers are longer than winters.
> > Those Ozzies just have bad luck.
>
> Now, but it is changing.

Sure, Milankovic will have his revenge,

Jan
(not holding my breath)

On Tuesday, 31 May 2022 at 11:59:13 UTC+2, Mikko wrote:

> No, Ptolemy's theory of the motion of Sun (or Earth -- Ptlemy could not
> determine which one is moving

What a great example of the obedience to the Laws of Nature,
announced by great Galileo.
Unlike Copernicus. For sure, Copernicus didn't understand
that the Laws of Nature are forbidding him what he did.

> but choose to describe his theory in terms
> of stationary Earth) did not use epicycles. Sun's motion was described
> as a non-uniform motion along an eccentric circle.

As it is from the point of view of an Earth observer, i.e.
all of us.

On 2022-05-31 11:41:52 +0000, J. J. Lodder said:

> Mikko <mikko.levanto@iki.fi> wrote:

>> Ptolemy left unanswered one important question: what is the correct
>> definition of the zero point of Aries for astrological purposes?
>
> Didn't they lock it in Aries?

Most astrologers in Europe and India use Ptolemy's works as the basis
of their astrology. But Ptolemy did not specify the exact origin of
the zodiac. In European tradition the first point of Aries is taken to
be the point of the veran equinox whereas in the Indian tradition
the signs are attached to the stars so that the longitudes of the fixed
starts are the same as in Ptolemy's time. Conseqently, in the Indian
tradition the signs roughly agree with the corresponding constellations
but in the European tradition they are off by nearly one sign.

Mikko

Mikko <mikko.levanto@iki.fi> wrote:

> On 2022-05-31 11:41:52 +0000, J. J. Lodder said:
>
> > Mikko <mikko.levanto@iki.fi> wrote:
>
> >> Ptolemy left unanswered one important question: what is the correct
> >> definition of the zero point of Aries for astrological purposes?
> >
> > Didn't they lock it in Aries?
>
> Most astrologers in Europe and India use Ptolemy's works as the basis
> of their astrology. But Ptolemy did not specify the exact origin of
> the zodiac. In European tradition the first point of Aries is taken to
> be the point of the veran equinox whereas in the Indian tradition
> the signs are attached to the stars so that the longitudes of the fixed
> starts are the same as in Ptolemy's time. Conseqently, in the Indian
> tradition the signs roughly agree with the corresponding constellations
> but in the European tradition they are off by nearly one sign.

Yes, te Age of Aquarius and all that.

Anyway, for what it is worth: the equation of time
was important for astrologers striving for precision
because time of birth was usually know in terms of solar time,
like two hours after noon,
while the positions of the planets were known with respect to the stars.

It is a tribute to the capabilities of those early Babylonian observers
that they were capable of discovering it,

Jan

On Wednesday, June 1, 2022 at 3:54:41 AM UTC-7, J. J. Lodder wrote:
> Mikko <mikko....@iki.fi> wrote:
>
> > On 2022-05-31 11:41:52 +0000, J. J. Lodder said:
> >
> > > Mikko <mikko....@iki.fi> wrote:
> >
> > >> Ptolemy left unanswered one important question: what is the correct
> > >> definition of the zero point of Aries for astrological purposes?
> > >
> > > Didn't they lock it in Aries?
> >
> > Most astrologers in Europe and India use Ptolemy's works as the basis
> > of their astrology. But Ptolemy did not specify the exact origin of
> > the zodiac. In European tradition the first point of Aries is taken to
> > be the point of the veran equinox whereas in the Indian tradition
> > the signs are attached to the stars so that the longitudes of the fixed
> > starts are the same as in Ptolemy's time. Conseqently, in the Indian
> > tradition the signs roughly agree with the corresponding constellations
> > but in the European tradition they are off by nearly one sign.
> Yes, te Age of Aquarius and all that.
>
> Anyway, for what it is worth: the equation of time
> was important for astrologers striving for precision
> because time of birth was usually know in terms of solar time,
> like two hours after noon,
> while the positions of the planets were known with respect to the stars.
>
> It is a tribute to the capabilities of those early Babylonian observers
> that they were capable of discovering it,
>
> Jan

There is drift jan not wobble.